The instant invention relates to a roofing plate made of a heat-insulating material for the planting of greenery on a roof.
An insulating board for the construction of a sub-roof which is built up similarly to roofing tiles and which is hung from a roof batten by an upper projection is known in DE-GM No. 1,932,832. An insulating board installed above overlaps the insulating board installed below over a short, upper area. Roofing tiles are hung from the insulating board by their projection from a crosspiece. Overlapping profiles are attached to the lateral edges of the insulating board to provide water-tightness at the lateral butt joints.
The thinness of the insulating boards creates a risk that the boards may be damaged on open construction sites, so that the sub-roof becomes permeable to water and low-temperature bridges are created. Today, relatively thick insulating layers are required, and the known boards are not well suited for. Surfaces have to be given an excessive and undesirable step configuration, creating the danger in steep roofs that the boards are precariously balanced because of the high tipping moment, and in flat roofs the danger that water may back up.
No mention is made of planting greenery on a roof in the context of the above known insulating boards.
In another insulating board for the construction of a sub-roof, known in DE-PS No. 23 49 710, the board engages between the roof battens and is supported on its lateral surface pointing to the eaves on the lower roof batten. An overlapping edge profile of complicated configuration is required here to ensure that the sub-roof is water-tight. Since the batten intervals vary from manufacturer to manufacturer, measuring for instance from 32 cm to 36 cm with roof pans, insulating boards of different dimensions must be used. This means special expense in the manufacture of, planning, storage of such boards. In connection with these insulating boards there is also no provision for planting greenery on a roof.
The planting of greenery on a roof can be required or useful for camouflage purposes in the military, for an improvement of the environment in urban areas, public buildings, or as an outstanding architectural element. For this purpose, mats of nutritive material are simply laid over existing roof surfaces and are fastened. Such mats last only for a limited time and must then be replaced. A sightly, lasting installation is not achieved in this manner.
Another known method for the planting of greenery on a roof consists in setting up individual boxes, vats, or the like designed especially for each application, on the roof, and to combine them with the substructure of the roof. This is expensive and time consuming, especially because of the great number of required connections to achieve tightness.
Another known roofing plate for planting greenery on a roof is in the form of a double depression interlocking tile or a roof pan with profiled edges which overlap when installed is disclosed in DE-OS No. 3,416,208. Near the lower end of the roofing tile a container, open on top, is built in to receive a nutritive medium for planting greenery on a roof. It is not possible to install a heat-insulated roof with such known roofing plates. To obtain heat insulation, additional measures would be necessary, such as for example, installing a sub-roof of insulating boards.